Amphoteric resinous condensation products prepared by reacting hcho with the reaction product of a water-soluble anionic linear copolymer and dicyandiamide compounds



Chemical Company, New Jersey No Drawing. Original application Oct. 5, 1960, Ser. No. 60,576, now Patent No. 3,223,751, dated Dec. 14, 1965. Divided and this application Feb. 23, 1965, Ser. No.

434,668 2 Claims. (Cl. 260-69) Newark, N..l., a corporation of This application is a divisional application of Ser. No. 60,576 Scllet, filed Oct. 5, 1960, now US. Patent 3,223,- 751.

The present invention relates to novel compositions of matter, their preparation from (a) anionic linear polymers and (b) cationic and amphoteric aminoplast resins and/ or their amino and amphoteric amino resin bases, and their utilization, particularly in the treatment of porous or fibrous substrates.

It is an object of the present invention to provide for novel treating agents, especially for porous or fibrous substrates which are obtained from anionic linear polymers and cationic and amphoteric aminoplast resins as well as their amino and amphoteric amino bases. It is a further object to provide for novel treating agents which when utilized in connection with said porous or fibrous substrates bring about enhanced properties of said substrates. Another object is to provide for procedures for preparing said novel treating agents. A still further object is to pro vide for improved leather, paper and textile treating agents which impart improved properties when applied to said substrates in such operations as retanning, tanning, dyeing, pigment dispersing, coating, textile finishing and adhesion. Other objects will become apparent from the detailed description given hereinafter. It is intended, however, that the detailed description and specific examples do not limit the invention but merely indicate preferred embodiments thereof since various changes and modifications within the scope of the invention will become apparent to those skilled in the art.

The above as well as other objects have been most unexpectedly and successfully achieved in the following manner. I have prepared and utilized in the treatment of various porous or fibrous substrates, resinous products which broadly can be described as mixtures of, complex salts of and condensates of (a) modified and unmodified water soluble anionic linear polymers and (b) water soluble and water dispersible cationic and amphoteric aminoplast resins. In the case of condensates of (a) and (b) above, I can utilize amino resin bases and amphoteric amine resin bases in lieu of the aminoplast resins. By the term mixtures, I means mixtures of completely neutralized anionic linear polymers and cationic or amphoteric aminoplast resins. By complex salts, I mean the salt formed by reaction between an anionic linear polymer in its free acid form or partially neutralized form and a cationic or arm photeric aminoplast resin. To form the complex salts, the

resin functions as a base.

The above products as will be shown susbequently are useful as pretanning agents, retanning agents, tanning agents and as auxiliary tanning agents for preparing improved leather products. Outstanding success has been found when leather resulting from metal salt tannages is treated with my products. For example, my products impart to the leather outstanding light fastness, increased fullness and loading, enhanced tensile strength and smooth grain. These products can be successfully used in such 3,322,726 Patented May so, rear diverse applications in the tanning industry as in the preparation of garment, shoe, glove, suede, sole and mechanical leathers. Also, it has been found that fat liquoring operations are greatly enhanced. This is of special value for leather wherein zirconium salts have been utilized because I have found that my materials prevent the zirconium from reacting with the fat liquoring agents.

My products impart improved properties to substrates other than leather. For example, when applied as dye assistants, improved color values and better leveling are obtained in many instances. Some of these products can be utilized as pigment dispersing agents, as agents in fiber and paper coating and as additives in paper making. When added to the beater, they serve as fillers and also improve wet resistance of the resulting paper. They have been found to contribute to enhanced fullness of the treated material, to supply special finishing effects and to exhibit binding and adhesive properties.

The application of my products in connection with a porous or fibrous substrate such as leather can be explained as follows. When a mixture or a complex salt of my two components, viz., the anionic linear polymer and the cationic aminoplast or amphoteric aminoplast resin is used, the mixture or complex salt is applied to the leather in the form of an aqueous solution or dispersion thereof by contacting the leather with said mixture. After the mixture or complex salt is colloidally absorbed to its greatest extent in the leather or other substrate, the pH is progressively lowered at intervals to a pH of about 2.5. In this manner, the cationic and anionic functional groups present in the mixture or complex salt of the anionic linear polymer and arninopla-st resin are activated and interreacted, thus bringing about precipitation in the fibers of the leather or other porous or fibrous substrate. Alternatively, when a mixture of my two components is'used, viz., a completely neutralized anionic linear polymer and a cationic or amphoteric aminoplast resin, the leather can be contacted with the two components successivelyand finally the two components are interreacted by lowering the pH to about 2.5 to bring about precipitation. Likewise, the two components which make up the complex salt, viz, the anionic linear polymer in its free acid or partially neutralized form and the cationic or amphoteric aminoplast resin can be applied successively to the leather thus forming the complex salt in the leather. Then the pH can be lowered as indicated above to bring about precipitation in the leather. It must be appreciated however, that the pH value of 2.5 represents an average since this value will vary somewhat depending upon the nature of the mixture or complex salt of my two components which is added. The lowering of the pH can be accomplished by the introduction of water soluble mineral acid-s, water soluble organic carboxylic and hydroxy carboxylic acids and water soluble acidic metal salts. Examples of the above agents utilized to lower the pH are hydrochloric acid, sulfuric acid, sulfonic acid, formic acid, acetic acid, glycollic acid, diglycollic acid, lactic acid, citric acid, tartaric acid, oxalic acid, aluminum sulfate, basic chrome sulfate and sodium bisulfate.

When a condensate of my two components is utilized, it is applied to the fibrous or porous substrate in a neutral form. Then the pH is progressively lowered at intervals to a pH of about 2.5. In this manner, the cationic and anionic functional groups present in the condensate are activated and interreact thus bringing about precipitation of the condensate in the substrate. Here again, it must be appreciated that the pH value of about 2.5 represents an average since this value will vary depending upon the nature of the condensate. Lowering of the pH can be carried out by using the same water soluble acids and water soluble metal salts referred to previously.

Whether mixtures, complex salts or condensates of my two components are applied to a substrate, impregnation is achieved through colloidal adsorption or through direct afiinity of the substrate for the treating agents depending upon the nature of the substrate.

It is known to utilize certain anionic linear interpolymers in the tanning of leather. For example, U.S. Patent No. 2,205,882, Graves, June 25, 1940, describes the use of partially neutralized maleic anhydridestyrene interpolymers as tanning agents. Also, it is known to utilize certain cationic aminoplast resins in the tanning of leather. However, the combination of these two classes of materials, as mixtures or complex salts to be precipitated in a substrate or as condensates to be precipitated in a substrate, has been found to bring about improved, indeed, superior results when compared with the use of the prior art indicated above. The outstanding lightfastness of leather treated with my products was most unexpected. This superiority is in constrast to the leathers treated with naphthalenic or phenolic synthetic tanning agents which have a deleterious effect on leather due to photochemical changes which they undergo. Moreover,

the use of my materials also results in products having diverse utilities as indicated above. Additionally, many of the anionic linear polymers and many of the aminoplast resins described herein are in themselves new compositions of matter which can be utilized as taught herein.

ANIONIC LINEAR POLYMERS The modified and unmodified water soluble anionic linear polymers can be described as follows. They are copolymers of maleic acid, maleic anhydride or itaconic acid and olefinic hydrocarbons which are copolymerizable therewith. The resulting polymer can be utilized in its free acid form or as a partially or completely neutralized ammonium or alkali metal salt, e.g., as the sodium or potassium salt. When the acid form of the copolymer is difficultly soluble or insoluble in water, then the partially or completely neutralized forms are used. In preparing the copolymers, useful comonomers for the maleic anhydride, maleic acid or itaconic acid are one or a mixture of the following ethylenically unsaturated monomers: ethylene, styrene, p-methyl styrene, vinyl ethers such as methyl vinyl ether, ethyl vinyl ether, propyl vinyl ether, vinyl esters such as vinyl acetate, acrylic esters such as methyl acrylate, ethyl acrylate, methyl tx-methylacrylatc, isobutylene, diisobntylene, acrylamide and substituted acrylamide such as butyl aciylamide. In the above polymers, the maleic anhydride, maleic acid or itaconic acid and the ethylenically unsaturated monomers which are copolymerizable therewith are present in approximately a 1:1 mol ratio. In the case of copolymers of salt of itaconic acid and acrylamide, from about one to three mols of acrylamide can be utilized per mol of itaconic acid salt.

The preparation of the above polymers is well known in the art and this invention is not to be limited by such preparations. Polymerization procedures which can be utilized can be found in, e.g., U.S. Patent No. 2,047,398, Voss et al., July 14, 1936; U.S. Patent No. 2,286,062, Condo et al., June 9, 1942; U.S. Patent No. 2,430,313, Vana, Nov. 4, 1947; U.S. Patent No. 2,490,489, Tauch, Dec. 6, 1949 and U.S. Patent No. 2,378,629, Hanford, June 19, 1945.

The above polymers if desired, can be modified such as by forming their amide ammonium salts or amide amine salts. Also, the polymers can be reacted with salts of sulfoaminomethane, and the modified amide ammonium salts'of the polymers can be further treated with salts of sulfohydroxy methane and if desired can be further treated with formaldehyde. These reactions are performed in equimolar proportions with regard to the reactive groups involved. However, this can be varied so as to obtain products of vaiying characteristics, i.e., products having characteristics lying between the unmodified and completely modifitd polymers. In other words, the polymers can be partially modified as well as completely modified as indicated above. Thus, by the expression, modified, I mean partially modified as well as completely modified anionic linear polymers.

These modified anionic polymers can be used in connection with cationic and amphoteric aminoplast resins and aminoplast resin bases as described herein for preparing stable solutions having cationic and anionic functional groups which can be interreacted by addition of acids. They can also be advantageously used by themselves in leather treatment whereby the stability under acidic conditions can be of importance in operations such as pretanning, tanning of pickled stock or when metal salt tannages are first submitted to an anionic retanning operation followed by a aminoplast resin treatment or with mixtures of other aminoplast resins and anionic linear polymers. Observations indicate improved tightness of the grain when applied on metal salt tannages.

In preparing amide ammonium salts of the aforesaid polymers, ammonia gas is passed through the polymer in its anhydride form at room temperature or at slightly elevated temperatures. Two mols of ammonia gas are utilized per anhydride group.

When preparing amide amine salts, primary or secondary amines such as ethanolamine, diethanolamine and propanolamine are reacted with the polymer in its anhydride form at, e.g., 50 C. to C. in an inert solvent such as dioxane or dimethylformamide. Two mols of amines are utilized per anhydride group. Of course, if further reaction of the amide amine salt is to be carried out, then only primary amines can be used in the preparation of the amide amine salt. The resulting water soluble compounds can be mixed with stable aminoplast resins to form stable solutions. The end use of the amide ammonium and amide amine salts is similar to those previously described when the free acids as well as the partially or completely neutralized linear polymers are used in conjunction with stable aminoplast resins. However, as the potential anionic property is weakened by the amide group, subsequent interreaction by acidification is of a lesser degree. Instead of a strong precipitate, only milky or colloidal or semicolloidal solutions are formed. Such forms of interreaction are desired particularly when better penetration and slower fixation in the substrate are required. The amide derivatives of the linear polymers are also suitable for condensation with aminoplast resins.

When modifying the polymers with salts of sulfoaminomethane, e.g., the alkali metal salts such as sodium and potassium, the following procedure can be used. The salt of sulfoaminomethane is reacted with a half salt of the polymer, i.e., a one-half neutralized polymer, which still has the remaining one free carboxylic acid group. Reaction is achived by heating and driving off the Water formed during reaction. One mol of the salt of sulfoaminomethane is utilized per free carboxylic acid group of the polymer. Also, monosubstituted derivatives of the salts of sulfoaminomethane can be used such as the sodium salt of sulfohydroxyethylaminomethane. These condensates demonstrate increased acid stability.

Other useful and improved condensation products of anionic character are obtained when salts of sulfohydroxymethane, e.g., alkali metal salts such as sodium or potassium, are condenesd with the amide ammonium salts of the anionic linear polymers heretofore described. One mol of the salt of sulfohydroxy methane is utilized for each amide group in the polymer. These anionic condensates can be further condensed under prolonged heating with formaldehyde which reacts with the ammonium salt to form methylol amine. One mol of formaldehyde is utilized per each ammonium salt group. The final condensate shows increased stability to metal salts and has good pigment dispersing and suspending qualities. When the amide ammonium salts of a copolymer containing approximately equimolar amounts of styrene and 'nylurea,

maleic anhydride are used in the condensation with the salt of sulfohydroxymethane, an acid stable anionic polymer is produced. Useful anionic polymers can also be produced when the amide group of the amide ammonium salt of the anionic linear polymer is condensed with itaconic acid. One mol of itaconic acid is utilized per amide group which is present in the polymer. It has been found that the alkali metal salts, e.g., sodium and potassium, of the condensate of itaconic acid and the amide ammonium salt of a polymer containing approximately equimolar quantities of ethylene and maleic anhydride are good pigment dispersing agents. When a copolymer containing approximately equipmolar amounts of styrene and maleic anhydride as amide ammonium salt is used in the condensation with itaconic acid, a condensate is produced which shows good stability at lower pH.

A particularly outstanding copolymer is obtained when from about one to three mols of acrylamide are copolymerized with one mol of itaconic acid or one mol of a substantially neutralized salt of itaconic acid, e.g., the sodium, potasium or ammonium salt in presence of a polymerization catalyst, e.g., potassium persulfate. Heating at about 75 C. for approximately 4 hours is sufiicient to bring about copolymerization. The resulting product is an outstanding dispersing agent and adhesive when utilized alone either in its free acid or substantially neutralized salt form. It can also be admixed with stable aminoplast resins for preparing stable solutions having cationic and anionic functional groups which can be interreacted by addition of acids. The copolymerization product of acrylamide and salt of itaconic acid can be modified through saponifination of the amide groups which are present to various degrees. This is accomplished by treatment with an alkali, e.g., sodium or potassium hydroxide.

An anionic linear polymer having outstanding dispersing properties will result. This product can be dried to form a white to tan easily water soluble material.

AMINOPLAST RESINS AND AMINO RESINS BASES The cationic aminoplast resins, the amphoteric aminoplast resins, and their amino resin bases and amphoteric amino resin bases can be described as follows. The cotionic aminoplast resins are prepared by interreacting or condensing an amino resin base with an aldehyde, preferably formaldehyde, or a compound which liberates formaldehyde such as paraformaldehyde, trioxane and hexamethylenetetramine. The amino resin bases can be characterized as low molecular weight nitrogen containing compounds which, by reaction between the hydrogen of the amine with aldehydes, form methylol derivatives in monomeric or polymeric form thus producing resinous materials of colloidal nature.

Examples of amino resin bases which are condensed with formaldehycles ore dicyandiamide, guanidine, guaurea, thiourea, biuret, melamine, ameline, amelide, cyanuric acid, guanamiue as well as their mixtures and derivatives. The aminoplast resins obtained as indicated above are generally characterized as cationic to various degrees, as water soluble or water dispersible and preferably should have a long and unlimited shelf life, i.e., should not undergo physical or chemical change upon standing for long periods of time. Examplary of these cationic aminoplast resins are those described in British Patent No. 777,827, June 26, 1957. The resins described herein are characterized by their excellent shelf life. This results from the elimination of free methylol groups of the resin by reaction with aminoplast bases such as those given above. Other useful cationic aminoplast resins are those set forth in US. Patent No. 2,847,- 396, Sellet, Aug. 12, 1958, i.e., the resins prepared in column 1, line 71 to column 2, line 15. The degree of cationic activity in the aminoplast resin is shown by interreaction with anionic materials and is related to the degree of polymerization and molecular size. Aminoplast resins which are strongly cationic in nature are the A resins described therein can be higher molecular weight resins having a high degree of polymerization. Aminoplast resins having a lesser degree of cationic activity have lower molecular weights resulting from a lower degree of polymerization. Also, the presence of carbonamide groups tends to reduce the degree of cationic activity.

The amphoteric aminoplast resins are cationic aminoplast resins which have been modified by introducing anionic substituents into them such as carboxy groups and sulfo groups. The nature of the anionic substituent taken in connection with the nature of the cationic substituents of the aminoplast resin will determine whether cationic or anionic properties will predominate in the amphoteric resin. That is, the amphoteric aminoplast resins can very in their nature from predominately cationic to predominately anionic resins. The reason for utilizing aminoplast resins varying in nature from cationic to amphoteric, i.e., from strongly cationic to weakly cationic is as follows. When strongly cationic resins are utilized in connection with the anionic linear polymers, whether as mixtures, complex salts or condensates, and applied to to a substrate such as leather and then precipitated with an acid, a fast inter-reaction occurs between the components, i.e., an immediate and heavy precipitate will be formed in the leather. On the other hand, when amphoteric aminoplast resins are utilized in connection with the anionic linear polymers, whether as mixtures, complex salts or condensates and applied to a substrate such as leather and then interreacted with an acid, a weaker and slower interreaction occurs between the components as compared to the reaction when a strongly cationic resin is used. This slower inter-reaction or precipitation is utilized when a more complete penetration is desired. Thus, when amphoteric aminoplast resins are utilized, an advantage is the fact that the acid sensitivity is of a lower degree.

Suitable amphoteric aminoplast resins are as follows. Any water soluble or water dispersible cationic aminoplast resin including those given above can be modified to form amphoteric resins by introducing either during or after their preparation anionic functional groups such as carboxylic and sulfo groups. Useful amphoteric aminoplast resins can be found in US. Patent No. 2,847,396, Sellet, Aug. 12, 1958. That is, the amino-modified stage modified as set forth in column 3, lines 9 to 38 of this patent. Likewise the resins obtained by carrying out stages one and two described in US. Patent No. 2,870,122, Sellet, Ian. 20, 1959 can be modified as set forth in column 4, lines 13 to 39 of this patent. The products prepared according to British Patent No. 777,827, June 26, 1957 are particularly suited for transformation into amphoteric aminoplast resins.

Other useful amphoteric aminoplast resins can be prepared by condensing unsaturated dibasic acids such as itaconic acid, maleic acid and maleic anhydride or their monoammonium salts with equimolar amounts of dicy andiamide in aqueous solution. Upon prolonged heating, e.g., at reflux for, e.g., four to six hours, condensation occurs simultaneously with saponification of the nitrile group. This has been demonstrated by infra-red analysis. Also, in the case of itaconic acid, the double bond disappears as indicated by infra-red analysis. This would indicate lactam formation. The above condensates, e.g., of itaconic acid and dicyandiamide, can be admixed with the anionic linear polymers previously described or alternatively condensed at elevated temperatures with said linear polymers. If desired, the condensates of dicyandiamide and itaconic or maleic acid or anhydride can be condensed with aldehydes. Preferably the condensates of itaconic ormaleic acid and dicyandiamide is condensed with from one to four mols of aldehyde, e.g., formaldehyde and then mixed or condensed with the anionic linear polymers.

Another type of aminoplast resin can be prepared by first preparing a mono ammonium or mono-primary amine salt of itaconic acid or maleic acid. The amine salts are obtainable from reaction with lower alkanolamines such as ethanolamine. One mol of this product is in turn reacted with one mol of an aldehyde, e.g., formaldehyde, resulting in the acid salt of the methylolated amine. An amino resin base, dicyandiamide, in equimolar amounts with regard to the itaconic or maleic acid, is then introduced and condensed with the methylolated amine. Through prolonged heating in presence of water further condensation occurs between the newly formed amine compound, and the acid thus yielding a lactam. Also, the nitrile group is saponified. These products when further reacted with an aldehyde, e.g., from one to 4 mols can be admixed with the aforesaid anionic linear polymers to produce stable materials for treating the various substrates referred to herein. Preferably the amphoteric resins and the linear polymers are utilized in their partially or completely neutralized state. The above condensation products prepared from the itaconic or maleic acids or anhydride possess a higher cationic functional property when compared with a condensate of itaconic acid and dicyandiamide alone.

Also, modified amino resin bases, e.g. the sodium or potassium salt of sulfomethyl dicyandiamide can be reacted with an aldehyde, e.g., from one to three mols of formaldehyde per mol of modified amino resin base and the resulting amphoteric aminoplast resin utilized in admixture or as a condensate with the anionic linear polymers. Sulfomethyl dicyandiamide is also known as (-cyano-guanidino) methane sulfonic acid:

Examples of useful amino resin bases which can be condensed with the anionic linear polymers are dicyandiamide, guanidine, guanylurea, urea, thiourea, biuret, melamine, ameline, amelide, cyanuric acid, guanamine, as well as their mixtures and derivatives. Examples of amino amphoteric resin bases which can be condensed with anionic linear polymers are the sodium salt of sulfomethyl dicyandiamide and condensates of dicyandiamide and itaconic acid or maleic acid or maleic anhydride.

When my two components are utilized as mixtures or as complex salts with the anionic linear polymers and subsequently precipitated upon a substrate by addition of an acid, they can be utilized in approximately equimolar amounts. However, this is not to be construed as a limiting relationship because either of my two components can be present in varying molar excesses over the other component. This will depend upon the final effects which are desired. For example, leather treated with a copolymer containing approximately equimolar amounts of styrene and maleic acid will receive dye rather poorly. However, even the presence of a small amount of aminoplast resin will enhance the affinity of the dye. Thus, as merely indicative, but not limiting, my two components when utilized as mixtures or complex salts can be present in a molar relationship of from 1:15 to 15:1 with regard to each other.

When my two components are utilized either as a mixture, complex salt or as a condensate in connection with .the treatment of a substrate the substrate is maintained in aqueous medium. Additionally, water soluble solvents, e.g., water soluble alcohols, glycols, esters and ethers can be present. My two components when utilized separately to form a mixture or as a complex salt or as a condensate can be added to the substrateas aqueous solution, aqueous dispersions or as dry solids whenever the components are of such a nature that they can be obtained in the form of solids. For example, the anionic linear polymersas well as the cationic aminoplast resins and their amino and amphoteric amino resin bases can be prepared as solids by removing the water, e.g., by boiling, roll drying of spray drying to form solid material. The solid material can be ground or flaked as desired. Likewise, the condensates of the above components can be utilized as solutions, dispersions or as solids.

CONDENSATES OF ANIONIC LINEAR POLYMERS AND AMINOPLAST RESINS AND AMINO RESIN BASES With regard to the preparation of condensates of my two components, which can be applied to a substrate, the following is set forth.

Cationic aminoplast resins, preferably those which have their methylol groups substantially blocked off, can be condensed with anionic linear polymers which have a free carboxyl group available for reaction with the available hydrogen of the cationic aminoplast resin. Provision must be made so that the resulting condensate has amphoteric characteristics. This can be accomplished by condensing one mol of aminoplast resin with one mol of an anionic linear polymer which preferably has its second carboxyl group neutralized. That is, one mol of aminoplast resin is utilized for each free carboxyl group of the linear polymer.

Water soluble anionic linear polymers in their free acid or as partially neutralized forms whether modified or unmodified, such as those heretofore described can be reacted with aminoplast resin bases such as those previously described. Thereafter, the resulting condensate can be subsequently reacted with an aldehyde, e.g., formaldehyde. For example, linear polymers which are water soluble as free acids or as their partially neutralized salts can be used as modifying agents for aminoplast resin bases such as dicyandiamide. When the two were dissolved in water in equimolar proportions and heated for several hours, the pH which at the start shows a pH value of 2.4, rose gradually to 4.6. Infra-red analysis showed disappearance of the nitrile group. Generally, a water solution or slurry in water of both reactants is first heated preferably near the boiling point of water. More heat is then applied to reach temperatures above C., preferably between to C. in order to drive off the water and to bring about condensation. The reaction product is then treated with aldehyde, preferably 3 to 4 mols of formaldehyde to produce an aminoplast resin of amphoteric character. The reaction product is then substantially neutralized and forms a stable solution.

Other amphoteric condensates can be prepared by condensing the aforesaid anionic linear polymers with modified aminoplast and amphoteric aminoplast resin bases, e.g., the sodium or potassium salts of sulfo methyl dicyandiamide or the condensate of itaconic acid or maleic acid or anhydride and dicyandiamide. When an amino base is used, subsequent treatment with an aldehyde, preferably 1 to 4 mols of formaldehyde, is utilized.

Some of the aforesaid products which are useful in particular as pigment dispersing agents are obtained when an aminoplast resin base, in particular dicyandiamide, is first condensed with, e.g., itaconic acid to form an amphoteric resin base having reactive primary or secondary amino groups. Then further condensation with anionic linear polymers as free acids or their anhydride is carried out. The amphoteric resin base and linear polymer are first dissolved in water, preferably in equimolar proportions. After evaporation of the water present, the condensation is carried through at temperature above 100 C. preferably between 110 to 120 C. The resulting condensation product is then neutralized to pH of 8.5 to 9.

Condensation products of similar characteristics can also be prepared by condensing a dicyandiamide maleic acid reaction product with said linear polymers. The above mentioned types of condensation products are particularly useful as pigment dispersants.

Other amphoteric condensates can be prepared by reacting amide ammonium salts of the aforesaid anionic linear polymers with methylolated amphoteric resins.

NATURE OF SUBSTRATE As previously indicated, my two components whether as a mixture, complex salt or as a condensate can be applied to many diverse substrates. Exemplary of these substrates are porous or fibrous substrates such as leather, paper, wool, cork, non-woven textiles or bats, such as felt and Masslin, woven textiles of cotton, wool, silk, rayon, regenerated cellulose, nylon, Dacron, polyacrylonitrile and others. When my two components are utilized as dye assistants they can be used in connection with the above indicated woven and non-woven textiles. Additionally, they can be used in connection with the dyeing of yarns and filaments. Synthetic yarns, filaments and woven and non-woven textiles can be treated with my components such as nylon, Dacron, polyacrylonitrile etc.

In the treatment of a substrate such as leather from about 3% to about 20% of my products are utilized based on the weight of the wet shaved leather.

Throughout this specification, wherever molar amounts of linear polymer are referred to this means one reoccurring molar group regardless of the specific reactive substitutents therein. For example, in a polymer obtained by copolymerizing equimolar quantities of it-aconic acid and ethylene, each reoccurring itaconic acid-ethylene group is deemed to be one molar group.

The following examples are directed to the preparation of mixtures, complex salts and condensates of my two components. It must be kept in mind that the mixtures can be applied to a substrate and then treated with acid to bring about interreaction and precipitation or else the substrate can be treated in succession with the two components after which the acid treatment is carried out. Likewise, in the use of complex salts, the complex salt can be applied to the substrate and then treated with acid to bring about interreaction and precipitation or else the substrate can first be treated in succession with the two components which react and form the complex salt after contact with the substrate and then treated with acid to bring about precipitation and inter-reaction.

Example I 126 grams of a maleic-ethylene co-polymer in its anhydride form and containing equimolar amounts of maleic anhydride and ethylene and 84 grams of dicyandiamide were dissolved in 540 grams of hot water. The resulting solution was refluxed under stirring for .5 hours at temperatures between 90 to 98 C. The 326 grams of Methyl Formcel (46% by weight aqueous solution) were then introduced slowly under stirring. The reaction mixture was then heated for 1 hour at 90 C. and subsequently neutralized to a pH of 7.5 By addition of acid to lower the pH, a white precipitate was formed.

Methyl Formcel is a commercial mixture containing 40% by weight formaldehyde, 53% 'by weight methanol and 7% by weight water.

Example 11 126 grams of a maleic ethylene co-polymer (in its ananhydride form) and containing equimolar amounts of maleic anhydride and of ethylene and 84 grams of dicyandiamide, were dissolved in 540 grams of hot water. The resulting solution was refluxed for 11 hours at temperatures between 81 and 97 C. Then 326 grams of formaldehyde (37% by weight aqueous solution) were added and reacted for /2 hour at 80 C. Thereafter, 64 grams of methanol were added and heating for /2 hour at 80 C. was carried out. The resulting reaction product was neutralized with caustic soda to a pH of 8.2. The liquid formed a stable viscous solution. This product was then spray dried to a white easily water soluble product. Under acidic conditions, inter-reaction between the amonic and cationic groups occurred as evidenced by a heavy white precipitate.

Example III A. 145 grams of an ethylene maleic copolymer in its anhydride form and containing equimolar amount-s of ethylene atnd of maleic anhydride were added to 500 cc. of hot water, and heated until dissolved.

84 grams dicyandiamide were added to the polymer solution and refluxing for 5 hours at 90 to 95 C. was carried out. The resulting reaction mixture was dehydrated and product heated for 2 hrs. between 110 C. to 120 C. for further condensation.

The reaction product was then dissolved in 600 cc. water and 326 grams of formaldehyde were added. The temperature was brought up to 90 C. to 95 C. and stirring in reflux equipment for 3 hours was carried out. The reaction product was then neutralized with caustic soda to a pH of 9.0. Addition of acid produced a heavy White precipitate.

B. 970 grams of a 25% by weight aqueous solution of a styrene-maleic acid copolymer in the form of its monosodium salt was mixed with 84 grams of dicyandiamide. The above polymer was obtained by copolymerizing equimolar quantities styrene and maleic anhydride. To the above mixture of polymer and dicyandiamide, 300 grams of water were added and the resulting material heated at about C. until a clear solution was obtained. Thereafter this material was spray dried. 308 grams of the powder resulting from the spray drying step was then heated at 120 C. for 3 hours. The resulting condensation product was introduced into a vessel fitted with a reflux condenser. 1400 grams of water were added and the condensation product dissolved in the water by heating for one-half hour at 80 to 90 C. When a solution was obtained, 243 grams of formaldehyde 37 by weight of aqueous solution) was introduced and further reaction carried out by heating for 4 hours at to C.

Example IV 145 grams of an anionic linear polymer (obtained by copolymerizing equimolar quantities of maleic anhydride and ethylene) in the form of its free acid was introduced into 500 cc. of water. Heat was applied until a clear solution was obtained. Then, 84 grams of dicyandiamide were introduced into the solution and refluxing for 5 hours at 90 to C. was carried out. Thereafter, the water present in the reaction product was evaporated oil and the remaining material further heated at 120 C. for 2 hours. The resulting product was clearly soluble in water and a 5% aqueous solution had a pH of 5.

211 grams of the product prepared above were dissolved in 600 cc. of water with the application of heat. The solution was then cooled to 25 C. and grams of sodium hydroxide (40 B. solution) were slowly added to the solution. During the addition, the temperature was maintained under 30 C. Then, 326 grams of a 37% by weight aqueous solution of formaldehyde and 32 grams of methyl alcohol were added and the solution stirred and refluxed at temperatures between 80 and 85 C. for 4 hours. Thereafter, the reaction product was cooled down and the product recovered.

Having described my invention, what I claim is new and desire to secure by Letters Patent is:

1. The condensation product of (A) from three to tour mols of formaldehyde, and

(B) one mol of a condensate of molar proportions of (1) dicyanidiamide, and

(2) a member selected from the group consisting of the tree acid form of, the partially neutralized ammonium salt form of and the partially neutralized alkali metal salt form of water soluble anionic linear copolymers, said copolymers containing approximately equirnolar amounts of at least one member of the group consisting of maleic 11 12 anhydride, maleic acid and itaconic acid and at polymerized with a comonomer selected from a least one other ethylenically unsaturated monomer group consisting of itaconic acid and salts of itacopolymerizable therewith with the proviso that conic acid, there are from 1 to 3 mols of acrylwhen said copolymer contains acrylamide coamide per mole of said monomer, and polymerized with a comonomer selected from a 5 (2) a member selected from the group consisting of group consisting of itaconic acid and salts of ita- (a) salts of sulfo methyl dicyandiamide, and conic acid, there are from 1 to 3 mols of acryl- ('b) condensates of dicyandia-mide with a memamide per mol of said monomer. her of the group consisting of itaconic acid, 2. The process of preparing an amphote-ric condensate maleic acid and maleic anhydride. which comprises reacting:

(A) from one to four mols of formaldehyde, and 10 References Clted (B) one mol of acondensate of UNITED STATES PATENTS (1) a member selected from the group consisting of 2,870,122 1/1959 Selle-t 260-69 the free acid form of, the partially neutralize 2,891,932 6/1959 Hankins 260-80.5 ammonium salt form of and the partially n 15 2,913,437 11/1959 Johnson 260-785 tralized alkali metal salt form of water soluble OTHER REFERENCES 'aniomc linear copolymers, said copolymers containing approximately equimolar amou t f t Interchemical Reviews, volume 5, No.4 Rowland, pages 'least one member of the group consisting of maleic 3-87 relied on.

anhydride, 'maleic acid alnd itaconic adcid and at 20 WILLIAM H. SHORT Primary Examiner least one other eth lenical unsaturate monomer copolymerizable tli erewith with the proviso that SAMUEL BLECH, Examine"- when said copolymer contains acrylamide co- HSCHAI Assistant Examiner 

1. THE CONDENSATION PRODUCT OF (A) FROM THREE TO FOUR MOLS OF FORMALDEHYDE, AND (B) ONE MOL OF A CONDENSATE OF MOLAR PROPORTIONS OF (1) DICYANIDIAMIDE, AND (2) A MEMBER SELECTED FROM THE GROUP CONSISTING OF THE FREE ACID FORM OF, THE PARTIALLY NEUTRALIZED AMMONIUM SALT FORM OF AND THE PARTIALLY NEUTRALIZED ALKALI METAL SALT FORM OF WATER SOLUBLE ANIONIC LINEAR COPOLYMERS, SAID COPOLYMERS CONTAINING APPROXIMATELY EQUIMOLAR AMOUNTS OF AT LEAST ONE MEMBER OF THE GROUP CONSISTING OF MALEIC ANHYDRIDE, MALEIC ACID AND ITACONIC ACID AND AT LEAST ONE OTHER ETHYLENICALLY UNSATURATED MONOMER COPOLYMERIZABLE THEREWITH WITH THE PROVISO THAT WHEN SAID COPOLYMER CONTAINS ACRYLAMIDE COPOLYMERIZED WITH A COMONOMER SELECTED FROM A GROUP CONSISTING OF ITACONIC ACID AND SALTS OF ITACONIC ACID, THERE ARE FROM 1 TO 3 MOLS OF ACRYLAMIDE PER MOL OF SAID MONOMER. 